A common technique for treating arterial stenosis has been surgical construction of a bypass conduit around the site of the occlusion. Bypass grafting with a vein or prosthetic graft, has been the dominant technique for arterial reconstruction. Endarterectomy is also performed as an alternative treatment method. An endarterectomy is defined as the physical separation and removal of the inner layer of the blood vessel wall, the tunica-intima, over the length of the blood vessel where the blockage is located. The blockage is thereby removed along with the tunica-intima from the wall of the blood vessel. After removal of the blockage and the tunica-intima from the vessel, a new tunica-intima grows to replace that portion of the tunica-intima that was removed.
A problem with current ring separators/cutters is that the tunica-intima is separated from the blood vessel for a distance past where it is to be severed. Hence, upon removal of the tunica-intima and the blockage, a significant portion of the tunica-intima remains displaced loosely around the circumference of the inner wall of the vessel. This loosely attached tunica-intima is believed to hasten restenosis of the blood vessel.